Pilot operated valves have long been used in a variety of applications. One application is that of pressure regulation wherein it is desirable to control the output pressure from a valve as a function of the input presure of a pilot signal.
Most frequently, it is desirable to control the output pressure from the regulating valve as a straight line function of the input pilot signal. In making such a valve with straight line response, a problem is the inability to eliminate the effects of a variety of variables such as input fluid temperature, output fluid temperature, and ambient temperature. Ambient pressure may also affect the system.
Vibrational loads in the environment in which the valve is employed and manufacturing tolerances of the valve components represent still other variables.
At the same time, it is desirable to provide a construction wherein hysteresis losses are minimized and which provides for minimum leakage of the input pilot pressure. It is also desirable that the valve have rapid dynamic response and a construction in which the linear relation between the output pressure and the input pilot pressure may be changed as desired. It is also desirable to design the valve such that it cannot be damaged when subjected to abnormal operating pressures.
The present invention is directed to overcoming the above stated problems and accomplishing the stated objects.